An exhibit at the Smithsonian National Air and Space Museum, Suited for Space, highlights these rarely seen film X-rays of astronaut gear from the 1960s and 1970s.

The skeletal images reveal the inner workings of what on the outside look like bulky, marshmallow-y suits. Glove design has changed the most since the Space Race era--it’s gone through six redesigns.

Other components, like helmets, have gone largely unchanged. The design from decades ago has retained its shape and structure and goals of keeping astronauts protected and electronically wired--similar hardware, however much the software has evolved.

“The inner workings and components show how they’ve come up with design solutions for very real problems, like keeping the air inside and keeping the spacesuit from blowing up,” curator Cathy Lewis tells Co.Design. “These are allowing the astronaut to do meaningful work and make movements.”

Conical rings around the knees, shoulders, and other joints allow free range of movement.

The more oft-seen exterior.

The least-changed component is the boot. Because no one has walked on another surface since the 1972 Apollo 17 mission, NASA hasn’t needed to upgrade its shape or the materials since.

Suited for Space is on view at the Smithsonian National Air and Space Museum in Washington, D.C., until December 1, 2013.

On View: Ghostly X-Rays Of NASA Spacesuits

The Smithsonian’s Suited for Space exhibit is a highly exposed showcase of astronaut garb and gear.

The U.S. lunar landing program wrapped up in 1972 with the Apollo 17 mission, the sixth time America accomplished the once-fantastical task of putting a man on the moon. Technology and the exploration it opens up seem to have expanded light years since—the Curiosity rover just celebrated its first anniversary of meeting Mars—yet as a Smithsonian exhibit now shows, spacesuit design has made no giant steps for mankind since the 70s.

A series of rarely seen X-rays on view at the National Air and Space Museum reveal the mechanical workings of decades-old spacesuits in high relief. Thing is, they don’t look so different from what today’s astronauts wear. Interestingly, this is not to say NASA has let progress fall to the wayside—it actually means that the first spacesuit creators may have simply nailed it.

"The inner workings and components show how they’ve come up with design solutions for very real problems, like keeping the air inside and keeping the spacesuit from blowing up," Cathy Lewis, curator of international space programs and spacesuits at the National Air and Space Museum, tells Co.Design. "These are allowing the astronaut to do meaningful work and make movements."

The spacesuit skeletons show how designers kept astronauts mobile with sets of conical ribbing around the shoulders and knees. They also built rubber restraint systems into the joint areas to preempt the problem of air displacement (flexing one arm and losing air space). Glove design has changed the most since the space race era—it’s gone through six redesigns—yet, or perhaps because, it’s the part of the suit that garners the bulk of complaints. Gloves are "a trade off," Lewis says, "between allowing the astronaut to have a tactile sense, and protecting the hand."

And the least-changed feature? The boot. (Oddly enough, this is the category that’s arguably changed the most in areas like sports and terrestrial exploration, like mountain climbing.) Because no one has walked on another surface since the 1972 Apollo 17 mission, NASA hasn’t needed to upgrade the boot’s shape or the silicone that was chosen for its lunar dust-repelling qualities. But Lewis predicts that the astro-boot will see a boost soon: "They’ll probably be planning for the next walk on another surface, be it a moon asteroid or Mars, and will look at different materials that will be easier to clean and maintain."

Suited for Space is on view at the Smithsonian National Air and Space Museum in Washington, D.C., until December 1.